Concrete agitator



Sept. 6, 1932.

G, l. L .QCKWOOD CONCRETE AGITATOR '7. 1930 2 Sheets-Sheet Filed Jan.

Patented Sept. 6, 1932 '.GnoRGnI. nocnwoon, 0F nonnLANnnnneoN Yconcnn'rn AGITATOR lapplcationled January 7,'1'930. Serial No. 41.9;079.

This invention :relates fto power driven agitators vadapted to beassociated with motor. Atrucks and the flike in yorderto keep theimaterial ina-sta'te :o'fagitation while Sit is :being transported froma central pointtothe .place of use. More specifically, fthe main idea isto provide .an improved, relatively simple,

powerful and eflicient :hydraulic zattachment 'for :agitating concrete:and `maintaining the proper consistency `While iit is being transported=in ftank Itrucksfandth'e like to a jpolnt Referring to 4theiaccompanying drawings,

i in which one illustrativefembodimentloffthe .invention fis shown:

Fig. 1 is a side .elevation sfhowing'an illusy trative form of theimprovements :mounted on a vmotor truck yof Aconventional design, thellatter being shown merely ingeneral'outline; F 2 fis .a top gpilan:view' of lthel mixing mechanism;

` F.ig. .f3 .is a frear end eelevation `of :the mixing ftank; Y

Fig. 4 is a front end elevation of .the tank;

Fig. 5 is a :longitudinal sectional -view of .the tank; v

AFig. 6 .is a transverse sectional view of the ftan rshownin Fig. l.;

Fig. 7 Eis 'fragmentary elevation partly in section, showing ia valvezfor :the hydraulic mechanism; land Fig. 8 .isa :fragmentary sectionalview throughapaddle employed in fthe illustrated form oifzthe invention.v

'The modern method-of handling concrete, especially in large vcities is"to mix the same at a centrallorsta'tionary plant and `transport it tothe point of use. Heretofore many types of tank wagons and motor truckshave been employed for this purpose. Also, various types of mechanicallydriven or `operated stirrers have been used in the tanks to keep themixture properly stirred and thereby maintain a more or less uniformconsistency. Other vise, the heavy aggregate would settle to the bottomandthe lighter constituents would rise tothe surface. The most commontype of stirrers now employedare driven by power ltake-oit :mechanismconnected to the motor truck engine `and this necessitates a that theywaste a greatdeal of power. This lly 'in foutline -'for mechanism.VInv-this fmechanism illustrated pump 4not shown, 'thebecau-seltima-yebe offconventionalLdesigniand,

. this instance, stantia'lly.semi-cylindrical:bottom to accom- -more oriless complex and other connections. 'Moreover, such 'mechanicallydriven stirrers are subjectto very great wear .and 1 experience .hasdemonstrated invention, therefore, aims v'to provide a very powerful,-smooth operating, efficient and durable hydraulic :stirrerthat is notsubject 'to the .foregoing :objections .Referring particularly to Vthelaccompanying drawings, theiillus'tratedforrn of the -improvements isshown 'as fbeing applied V:to a motortruck 10 which yis showny in Fig. 1'merep .the sake zof illustration. `Such'trucks are often `providedwithfa pump for operating a hydraulic :bod-,y ldumping example, thehydraulic iis adaptedfto beoperfated =by a -pump of this type for. aseparate pump being eliminatedv yhence, `fo.rms no part/of thepresentiinvention.

In .accordance with .thiis finvention, there `is shown :a itank -1'1pivotally mounted on the rearend iof ithe chassis frame ofthe truck.'This ftank vmay be lof various shapes, but in it is shown as having 1aslibmodate the stirring mechanism :later 5to =be described. Therear endofthe tank `is conveniently -closed by a hinged gate `lQadapted to belatchedinzclosed 'positionfsoas to vpreventthe mixture fromescaping=intransitand :this gatev maybe opened fordumping theimiX- ture,:it being understood, ftha't any-,ordinary fdumping mechanism fis'adapted' .to .be femp'l'oyed for tilting yfthe tank. Illustration ofsuch mechanism is funnecessaryin Athis example.

` VReferringto Figs. 1,:2and 5,V a Vstirring :shaft 113 Lis shown -as`being ljournaled 1in ithe' endwa'llsof the Stank and coaxialthereo'f,one

end projecting beyondthe forwardiend wall fof the tank.

jOn this shaft within the tank :there lare showntwo paddle-carrying:mem-

bers i4; conveniently 1arranged fnear the oppositeeendsfof the tank-andeach having a plurality ofrarmsbetween opposite Vones offwhich' `paddlemembers 15 are ijournaledso:as -tofos- .cillate v`.with .the :arms Thesepaddles .are

arrangement :of gears i' preferably bearings for the paddles is shown atthe endsk of the radial paddle arms. ln this instance, bearing blocks 16are secured on opposite sides of eacharin and terminals of the paddlesare journaled between them. As will be seen Fig. 8, each block 1Gpresents beveled faces providing abutments for the sides of the paddles,the arrangement being such thatthe paddles may swing from one side tothe other or be reversed as indicated in dotted lines in Fig. 8. bladesare longer than that, when the movement of the paddle arms is reversedthe resistance offered by .theA concrete mixture will be greater abovethe pivot points of the paddles than it pivot points and therebycausethem to swing the lower portions so against the other beveled faceof the abutlt will be understood that there between the ends of the topermt ment blocks. is suiicient clearance paddlesand the wall of thetank the paddles to swing through an arc of 30 or f chanical efficiency.

las

to Y get the ploying any gearing and power take-off Y' mechanismforoscillating the shaft, power is stirrer shaft 13. The

to it through one or In this instance,

herein delivered directly more hydraulic cylinders. a double actingdrive is shown, two horizontally alined hydraulic cylinders 17asecuredto the Vfront wall of the tank. Referring to Figs. l, 2 and l, a pistonrod 18 projects from thefhydraulic cylinders and is engaged by a rockerarm ltsecured to the arms is here shown as projecting through a slottedcoupling member 2O on the piston rod (Fig. 4)

to and exhausted from the outer ends of the cylinders. Herein,- astorage reservoir 21 for the oil under pressure is mounted on thechassis frame and a conduit 22 extending to j the hinged end of the tankand back to the front is connected to deliver the liquid to a cylinderthrough one of the branch conduits 23 through a four-way valve and anexhaust conduit 25 which extends to the hinged end vof the mixing tankand back to the intake of the hydraulic pump (not shown), on the truck.The exhausted liquid is pumped back into the storage reservoir through aconduit 26. The conduits 22 and 25 are preferably flexible at the rearend of the chassis so that they -matically toy control the The upperportions of the paddle' will below vthey The idea of reversing thepaddles is` maximum stirring action on both I strokes and to utilize allof the power de-V there being can swing with the tank as it isbeingdumped bythe usual'hydraulic` dumping mechanism (not shown) thus,enablingl the stirring mechanism to work while the material is beingdischarged. Of course, the conduits may be flexible throughout theirlengths or they may have swivel joints.

The four-way valve is adapted to be operated by the piston rodcouplingQO autoi admission and exhaust of liquid. Herein, avcrankarm 27is fixed on thefvalve stein and is connected to be oscillateLV by aT-shaped member 28 slidably mounted on the front end wall of the behindthe `pistonrod and presenting forwardlybent ears or projections 29 inthe path of the coupling member 20. The design is such that the valve isshifted as each piston nears the end yof its stroke in much the samefashionas an engine valve. Of course, the valve actuating means vmay bewidely varied.

Y It will be understood that the tank is filled with ready mixedconcrete while the stirrer is idle, the operation of the hydraulic pumpbeing controlled Vin the usual manner or like such pumpsare controlledfor hydraulically operated dump bodies.' vAs soon as the tank is lledthe stirring mechanism may be set in operation by starting thepump andthe apparatus requires no further attention until tlie load is dumped.The stirrers are adapted "2.

wear and the paddles operate to stir the conl- 'is tents of the tank inboth directions. 'In short, the mechanismV is so designed as to utilizea minimum of power to produce maximum stirring. v

From the foregoing description, it will be 'f seen .that theinstallation can be made at a relatively low cost. lThere are Anodelicate parts that are apt to get out of order or to require quickreplacement. The installation requires no special chassis design.

Obviously, the present invention isnot re- Y stricted to the particularembodiment thereof IOil or other liquid is preferably admitted Y hereinshown and described. Moreover, it is not indispensable that all thefeatures of the invention be used conjointly, since they i may beemployed advantageouslyin various .combinations and sub-combinations..

What I claim is:

l. In a vehicle for"v transporting concrete .stirrer arms; and hydraulicmeans for oscif.

lating said stirrer shaft.

2. In a vehicle for transporting concrete and the like, a substantiallysemi-cylindrical tank mounted r`on the chassis thereof; an

oscillatable stirrer with-inthe tank; ajshaft carrying said stirrer andprojecting through one wall of the tank; a rocker arm secured to saidshaft; a pair of hydraulic cylinders having pistons arranged on oppositesides of said shaft and contacting with said rocker arm; and automaticvalve means to control the operation of said pistons so as to oscillatesaid stirrer. l

3. In combination with a vehicle of the character described, a tankhaving a substantially semi-cylindrical bottom; a stirrer shaftjournaled in the opposite ends of said tank substantially coaxiallythereof; a. plurality of radial stirrer arms connected to said shaftadjacent to the opposite ends of the tank; reversible paddles pivotallyconnected to opposed pairs of said arms; a rocker arm connected to theforward end of said shaft; a pair of hydraulic cylinders below saidrocker arm each having a piston connected to actuate said arm; a liquidsup- Y ply tank; a conduit connecting said tank to each of saidcylinders; a multi-way valve in said conduit; and automatic means tooperate said valve so as to admit liquid to one cylinder and exhaustliquid from the other.

4. In a vehicle for transporting concrete and the like, a substantiallysemi-cylindrical tank mounted on the chassis frame thereof; a shaftjournaled in the end walls of said tank and arranged substantiallycoaxially thereof; paddle arms carried by said shaft; a plurality ofpaddles pivotally mounted on said arms; a rocker arm connected to saidshaft upon the forward end of said tank; a pair of horizontal hydrauliccylinders mounted on the front end of the f tank and having pistonscoacting with said rocker arm; a piston rod connecting both of saidpistons; valved conduits for admitting and discharging liquid to andfrom said cylinders; and valve operating mechanism including a slidablemember on the tank operable by the piston rod; and a crank arm on thevalve whereby to admit liquid to one cylinder while liquid is beingexhausted from the other cylinder and thereby oscillate said paddlescontinuously and automatically in said tank.

5. In a vehicle for transporting mixed concrete and the like, a tanktiltably mount ed on the chassis frame; an oscillatable agitator in thetank having a shaft projecting through one end wall; a rocker arm on theshaft; hydraulic operating means secured to the tank wall and'connectedto said rocker arm; a pressure tank on the chassis frame connected tosupply liquid to said hydraulic mechanism.

6. In combination with a tank vehicle for transporting mixed concreteand the like, an oscillating stirrer comprising aV shaft having radialarms; vreversible paddles journaled between said arms; and bearingblocks forming abutments for the paddles, the widths of said paddlesabove their pivotal axes being greater than that below their axeswhereby to cause the resistance offered by the mixture automatically toreverse the paddles when their direction of movement is reversed.

In testimony that I claim the foregoing as my own, I have hereto aiiiXedmy signature, Y Y

GEORGEv I. LOCKWOOD.

for said paddles presenting beveled faces

